Liquid Extraction of Carnosic Acid from Rosemary

The extraction conditions for carnosic acid from rosemary were studied using response surface methodology.The results indicated the optimum condition for preparing this liquid extract were ethanol concentration of 60%,oil/water ratio of 7.6,ethanol-vaporizing temperature 65 ℃,under which the content of carnosic acid was 14.91% and the extracts showed high antioxidant activity.